Square markers

Enabling marker tracking Creating markers Adjusting marker tracking

Cornerstone supports the use of 2D markers which can be used to track objects on the screen. The marker information can be accessed through the Cornerstone C++ API, TUIO stream, and XML stream.

Overall workflow

1. Create markers using the MarkerFactory application. Make sure that you pass the division (basically the data density) to the MarkerFactory application. MarkerFactory is distributed with Cornerstone and is located in bin folder. Instead of generating markers yourself, you can also download pre-generated markers as PDF-files from these links: 3x3 markers (32 unique codes) and 4x4 markers (4096 unique codes). These packages provide all unique codes for 3x3 markers and 4x4 markers. The physical size of the 3x3 markers is smaller than the 4x4 markers, but they can only represent a fraction of the unique codes.
2. Print out markers using any software that can open and print PNG files (PhotoShop, Gimp, Mac OS X Preview, etc.)
3. Enable marker tracking in OSD with the correct marker parameters. For square markers the options are 3x3, 4x4, 5x5 or 6x6 markers.
4. Use markers in your application
   • With Cornerstone SDK
   • With TUIO
   • By parsing XML stream

You may also want to check two FAQs about finger tracking with markers and marker image burn-in.